Telephone



G. B. RILEY.

TELEPHONE.

D APPLICATION FiLED APR. 26, 21. 1,432 623, Patented Oct. 17, 1922,

A 2 SHEETSSHEET l.

G. B. RILEY.

TELEPHONE.

APPLICATION FILED APR. 26. I921.

Patented Oct. 17, 1922..

2 SHEETS-SHEET 2..

Patented (Oct. 17, 11922.

NETE STARS GEORGE BAKER RILEY,

OF LONDON, ENGLAND.

TELEPHONE.

Application filed April 26,

To all'wizom it may concern:

Be it known that I, GEORGE BAKER RILEY, a subject of the King of Great Britain, residing at London, England, have invented new and useful Improvements Relating to Telephones, of which the following is a specification.

This invention relates to telephones and more especially to telephones used on motor vehicles, railway trains, on board ship, on air-craft, in private houses, oflices and warehouses, and in other positions where it is advantageous to avoid holding in the hand or applying to the person, the transmitting or receiving instrument, or both of such instruments.

In my improved telephonic apparatus, the sound waves are directed to or from a vibratory diaphragm by means of a sound concentrator or reflector comprising a parabolic or other suitable concave surface formed by a straight generating line which has a focus lying substantially on the surface of the diaphragm of the telephonic instrument, and the space within said concave reflecting surface 1s enclosed by means of a flexible diaphragm which is protected externally by a perforated screen, e. g., of wire gauze, perforated wood, ebonite, vulcanized fibre or like material.

By this means, it is possible both to prevent resonance effects When a receiver and a transmitter are arranged side by side and also to prevent the production of a muffled or megaphone quality of sound, such as is likely to occur with cup-shaped reflectors.

By my invention I am enabled to reproduce very loudly at the receiver the sounds transmitted, the reproduced sounds being free from the metallic twang heretofore frequently noticeable in loud speaking telephonic instruments.

In the accompanying drawings, I have shown how my said invention may be conveniently and advantageously carried into practice. In these drawings Figure 1 is a front elevation of a telephonic apparatus constructed' according to my invention.

Figure 2 is a plan view of the same with the cover raised.

Figure 3 is a vertical central section of the reflector on the line X, X, Figure 2.

Figure 4 is a vertical central section of the cover of the microphone casing, drawn to an enlarged scale.

1921. Serial No. 464,651.

Figure 5 is a tion.

A is the case of the instrument, which is here shown as having a hinged lid B bearing a multi-point switch C, e. g., for selecting the station to be communicated with, and a switch D corresponding to the hook-switch of an ordinary internal telephone. E is a buzzer. These switches and apparatus and also a transmitter F and a receiver Gr may be connected in a'circuit with other sets of instruments in any suitable known manner. The instruments may be of any suitable known construction.

The transmitter F, preferably a microphone, is supported on the base of the case by means of a bracket H and has its diaphragm side pointing inwards towards the centre of a reflector J consisting of a concave sheet of metal bent to a curve such that its focus lies on the surface of the microphone diaphragm. The position of the reflector is made adjustable by allowing its outer edges to fit into slots K, K in the side walls L, L of the compartment of the case in which the transmitter is arranged, so as to bring its focus into the desired position. The wall M of the casing of the transmitter F facing the reflector J is provided with perforations N, N which are flared or bell-mouthed, as shown in Figure 4.

The outer wall of the compartment of the case A containing the transmitter is formed with an aperture 0 closed on its inner side opposite the concave reflector J by means 0' a cover of wire gauze P supported on a wire frame Q and having arranged on its inner side a diaphragm R of paper, soft india rubber, or similar homogenous material. By this means, the sound Waves impinging on the cover P and diaphragm R are transmitted to the air in the transmitter compartment and impinge on the reflector or concentrator J whereby they are reflected towards the perforated wall N of the transmitter casing. As the reflector J has a straight generating line, it will have its focus in the form of a vertical line, so that the group of perforations N, N may be advantageously extended upwardly and downwardly and contracted laterally to cor. respond.

In Figure 5, there is shown an alternative means of adjusting the reflector S relatively to the transmitter F. Here the reflector has secured to its rear surface a screw threadplan illustrating a modificaed stem T which extends through a hole in the partition wall V and has lock nuts W, W adapted to engage opposite sides of such partition. By means of the nuts W, WV the reflector can be adjusted as required relatively to the transmitter F. The inner wall of the transmitter casing is here shown as provided with a horn 1. The wall of the casing of the transmitter F facing the reflector S is provided with flared or bellmouthed perforations as shown in Fig. 4.

The receiver G shown in Figure 2 is provided with a horn 5 in the form of a cone of small angle with a straight generating line. The outer end of this horn registers with an aperture 6 formed adjacent to the aperture 0 in the side wall of the casing A. This aperture 6 may be closed on the inner side by a wire gauze diaphragm 7.

It is obvious that if desired, the improved reflecting devices above described may be applied to telephonic receivers, the diaphragm of the receiver being arranged in I the same plane as the diaphragm of the transmitters above described.-

What I claim is 1. The combination, with a telephonic instrument comprising a vibratory diaphragm, of a concave sound reflector, which has its curved surface formed by a straight generating line and which has a focus lying substantially on the surface of the diaphragm of the telephonic instrument, which diaphragm faces the curved surface, a flexible diaphragm of homogenous material enclosing the space within said concave reflector, and means for protecting said flexible diaphra m.

2. The combination, with a telephonic instrument comprising a vibratory diaphragm, of a concave sound reflector, which has its curved surface formed by a straight generating line and-which has a focus lying substantially on the surface of the diaphragm of the telephonic instrument, which diaphragm faces the curved surface, a flexible diaphragm of homogenous material enclosing the space within said concave reflector, and a perforated protective screen arranged on the outside of said flexible diaphragm.

3. A telephonic apparatus comprising a vibratory diaphragm, a concave sound reflector which has a straight generating line and is arranged with a focus lying substantially-on the surface of the vibratory diaphragm, a flexible diaphragm enclosing the space within said concave reflector, a perforated screen arranged outside said flexible diaphragm, and means for adjusting the position of the sound reflector relatively to said. diaphragm.

4. The combination, with a telephonic instrument comprising a vibratory diaphragm, of a concave sound reflector which has a straight generating line and is arranged with a focus lying substantially on the surface of said diaphragm, a support connected to said telephonic instrument and a screw threaded stem and lock nuts adjustably connecting said reflector and said support.

5. The combination, with a telephonic instrument comprising a vibratory diaphragm, of a casing to said diaphragm, such casing having a plurality of outwardly flared holes, and a concave sound reflector which has its curved surface formed by a straight generating line and which has a focus lying substantia ly on the surface of the diaphragm of the telephonic instrument.

6. The combination, with a telephonic instrument comprising a vibratory diaphragm, of a concave sound reflector, which has its curved surface formed by a straight generating line and which has a focus lying substantially on the surface of said diaphragm, and a horn forming. a conduit for sound waves between said diaphragm and said reflector.

7. The combination, with a telephonic instrument comprising a vibratory diaphragm, of a concave sound reflector which is arranged with a focus lying substantially on the surface of said diaphragm, a support fixed to said telephonic instrument, a screw threaded stem and lock nuts adjustably connectin said reflector and said support, and a flexible diaphragm enclosing the space within said concave reflector.

8. The combination, with a telephonic instrument comprising a vibratory diaphragm, of a concave sound reflector which is arranged with a focus lying'substantially on the C. F. MURPHY, 

